The stress field for a screw dislocation near cavities and straight boundaries

نویسندگان

  • V. A. Lubarda
  • X. Markenscoff
چکیده

The stress distribution and dislocation forces for screw dislocations near cavities and straight boundaries are examined, depending on the selected cut used to impose a displacement discontinuity and create a dislocation. The location of the equilibrium dislocation position is determined in each considered case. The slip-induced stress amplification in thin ligaments between a cavity and a straight boundary, between the inner and outer surface of an eccentric hollow cylinder, and between two approaching cavities in an infinite medium are calculated. It is shown that in the limit of vanishingly small ligament width d , the shearing stress amplifies at the order of d . # 2002 Elsevier Science B.V. All rights reserved.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

An elastoplastic theory of dislocations as a physical field theory with torsion

We consider a static theory of dislocations with moment stress in an anisotropic or isotropic elastoplastical material as a T (3)-gauge theory. We obtain Yang-Mills type field equations which express the force and the moment equilibrium. Additionally, we discuss several constitutive laws between the dislocation density and the moment stress. For a straight screw dislocation, we find the stress ...

متن کامل

Analytical Stress Solutions of an Orthotropic Sector Weakened by Multiple Defects by Dislocation Approach

In this article, the anti-plane deformation of an orthotropic sector with multiple defects is studied analytically. The solution of a Volterra-type screw dislocation problem in a sector is first obtained by means of a finite Fourier cosine transform. The closed form solution is then derived for displacement and stress fields over the sector domain. Next, the distributed dislocation method is em...

متن کامل

On the Non-Uniqueness of Solution for Screw Dislocations in Multiply Connected Regions

It is well-known that the solution for a straight dislocation in an infinite medium does not depend on the cut along which the displacement discontinuity is imposed. This is also true for a semi-infinite medium, or any simply-connected region. The stress and strain fields, energy and dislocation forces are the same regardless of the cut. Only displacements differ in the region between the two c...

متن کامل

Development of Mathematical Model for Controlling the Drilling Parameters with a Screw Downhole Motor

Article presents results of study on possibility of increasing the efficiency of drilling directional straight sections of wells using screw downhole motors (SDM) with a combined method of drilling with rotation of drilling string (DS). Goal is to ensure steady-state operation of SDM with simultaneous rotation of DS by reducing the amplitude of oscillations with adjusting the parameters of dril...

متن کامل

Multiple moving cracks in an orthotropic strip sandwiched between two piezoelectric layers

In this paper, the solution of a moving Volterra-type screw dislocation in an orthotropic layer, bonded between two piezoelectric layers is obtained using complex Fourier transform. The dislocation solution is then employed as strain nuclei to derive singular integral equations for a medium weakened by multiple moving cracks. These equations, which are classified as, Cauchy singular equations, ...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 2003